1. Field of the Invention
This invention relates in general to scaffolding and shoring systems such as those used by building contractors, maintenance, repair personnel and others who are required to work on, build, paint and/or repair buildings and other structures. More particularly this invention relates to an attachment stud adapter for a safety guard rail for a conventional scaffolding or shoring system.
2. Discussion of Related Art
Conventional scaffolding or shoring(g systems have two spaced apart upright members secured in proper upright position by side crossed braces. In scaffolding systems, floor boards extend between the upright members and set upon horizontal supports provided on each upright member so that workers can stand and work on the stable, elevated, temporary flooring. however, workers and equipment still occasionally, for one reason or another, fall through the unprotected open space between the floor and the crossed braces of the scaffolding, resulting in serious injury. Consequently, OSHA, a federal regulatory health and safety agency, has imposed regulations on the industry that require suitable safety guard rails be installed on scaffolding systems to obstruct the open spaces between the braces.
In conventional shoring and scaffolding arrangements, the vertical support elements often are reinforced and stabilized by the use of additional crossed braces extending between them. Typically, these braces are secured to the vertical supports by bolt and nut assemblies with the bolts or studs, typically being welded or otherwise rigidly secured in fixed positions to the vertical support. With such arrangements, there has been at best difficult and limited flexibility in the positioning of the connection between the brace and the support.
Consequently. conventional guard or safety rail constructions have their drawbacks. For example, installation of safety rails is often difficult, time consuming and frustrating because of typical, minor dimensional variations in scaffolding systems. Furthermore, workers often quickly assemble the scaffolding system high above the ground. Thus, complex guard rails and attachment devices increase the likelihood of an accident in such an environment. Complex attachment devices are also more likely to jam, or become nearly impossible to remove, when they become dirty or when corrosion sets in. Therefore, workmen commonly ignore the installation of safety guard rails, despite the federal requirements for their installation. Moreover, conventional scaffolding systems do not have retaining studs long enough to secure both the required cross braces and guard rails.
One previously recognized solution, such as a guard rail which has C-shaped attachment clamps, has the disadvantages of not being universal enough for all applications and having a multitude of moving parts and a relatively high cost.
The below-referenced U.S. patents disclose additional solutions that were at least in-part satisfactory for the purposes for which they were intended. The disclosures of all the below-referenced prior United States patents, in their entireties are hereby expressly incorporated by reference into the present application for purposes including, but not limited to, indicating the background of the present invention and illustrating the state of the art.
U.S. Pat. No. 4,004,393 discloses a shoring or scaffold system which uses demountable stacked scaffold sections, each having a pair of spaced-apart end frames that are demountably cross-connected with respect to each other. To provide strength and support rigidity, vertically adjustable, bracing members are utilized to extend from the end frame of a lower section across and in an interconnecting relation with an opposed end frame of an upper section. These bracing members have at one end a pivot mounting which connects to a horizontally extending connecting member of a frame of one section and at the other end have a latching arm which is provided with a group of spaced-apart latching holes. The latching holes latch with a single latching pin and latch keeper element which are attached to a secondary leg member of the opposed frame.
U.S. Pat. No. 5,145,030 discloses a guard rail post comprised of an elongated member having securing means comprised of a U-shaped channel and a post pin for securing a guard rail post to a vertical support member of the scaffold, positioning means for mounting the guard rail post in fixed relationship to a scaffold work platform, and connecting means which includes pins having flip locks for connecting guard rails to the post at a fixed distance above the work platform.
U.S. Pat. No. 4,430,019 discloses a wedge-and-bolt connector assembly for adjustably fixing a stud to a slotted thin-walled structure or the like for use in a scaffolding or shoring system to connect braces to vertical support elements. The support elements have T-slotted channels formed therein. The connector assembly includes a stud having a T-shaped head adapted to be received in a channel and a shank extending through a channel slot away from the head. The stud shank is formed of two parts, a stud section and a connector or extension section threadedly engaged to the stud section. The free end of the stud extension section may have a toggle thereon for securing the brace to the stud shank. In lieu of the toggle, a wedge may be provided with an L-shaped slide-lock extension having a first leg and a second leg. A free end of the stud is adjacent to the leg when in the locking position.
U.S. Pat. No. 4,111,579 discloses a scaffold fitting attached to a scaffold tube which has a generally U-shaped clamping lever secured by a screw which passes through an intermediate aperture in the lever and which can be tightened to urge one end of the layer against a flanged member to clamp the latter directly against the scaffold tube. The free end of the lever has an arcuate abutment face which rests against the scaffold tube.
In embodiments disclosed in the above-referenced patents, a device for connecting additional members to scaffolding and/or shoring is disclosed. Nevertheless, these systems generally have the disadvantage that they do not work well with a multitude of conventional scaffolding and/or shoring systems. Further, as indicated above, these systems generally have the disadvantage that they are costly and complex to manufacture and operate.
What is needed therefore is device for attaching additional members, like guard rails, to existing scaffolding and/or shoring systems that is simple and easy to use in nearly any environment. Further, what is also needed is a cost effective attachment device for such systems.